Backhoe



J. S. PlLCH July 14, 1964 BACKHOE Filed March 7, 1965 INVENTOR. JOH N 5. 'P I LC; H

y z i W AT TOPNEY United States Patent 3,140,785 BACKHOE John S. Pilch, Ware Machine Works, Inc., P.O. Box 140, Ware, Mass. Filed Mar. 7, 1963, Ser. No. 263,507 5 Claims. (Cl. 214138) This invention relates to trenchers, backhoes, or the like, and has particular reference to the provision of new and improved means for varying the power and the speed of operation of such apparatus by varying the effective length of the dipper stick of the apparatus.

At certain times during the operation of a trencher, backhoe, or the like, additional power is desired. At certain other times during the operation of such apparatus, additional speed of operation is desired.

It is an object of the present invention to provide new and improved means of the type set forth, which new and improved means supplies this additional power, when desired, and this additional speed, when desired.

Another object of the invention is to provide new and improved means of the type set forth, which supplies this additional power or speed by varying the leverage of the apparatus which it accompanies.

Another object of the invention is to provide new and improved means of the type set forth which may be controlled either manually or automatically.

Another object is to provide new and improved means of the type set forth, which supplies such additional power or speed as may be desired by varying the effective length of the dipper stick of the apparatus which such means accompanies.

Another object is to provide new and improved means of the type set forth which acts such as to vary the distance between the pivot point of the boom to the dipper stick, and the pivot point of the dipper stick pivoting hydraulic means to the dipper stick.

Another object of the invention is to provide new and improved means of the type set forth for extending or retracting said pivot points in minute increments.

Other objects and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawings. It will be understood that changes may be made in the details of construction and arrangement of parts shown and described, as the preferred form of the invention has been given by way of illustration only.

Referring to the drawings:

FIG. 1 is a side view of a form of the invention in operative position upon a trencher; and

FIG. 2 is a sectional view taken on line 2-2 of FIG. 1, looking in the direction of the arrows.

Referring more particularly to the drawings, wherein similar reference characters designate corresponding parts throughout, the device illustrated comprises a boom pivotally connected at 11 to a support 12 which, in turn, is pivotally connected at 13 to a tractor or the like. Hydraulic power for the apparatus is furnished by said tractor or the like. The end of the boom 10 opposite to that pivotally connected to said support 12 is pivotally connected at 14 to the dipper stick 15.

Said boom 10 is adapted to be raised and lowered by the hydraulic jack 16 which is connected adjacent its opposite ends at 17 and 18 to the boom 10 and the support 12, respectively.

The dipper stick is pivotally connected at 20 to the bucket 19 and is, further, connected adjacent its opposite end to the slidably-mounted box-section dipper-stick extension 15a. Bucket 19 is pivotally connected at 21 to the link 25, which link 25, in combination with the second link 24 which is pivotally connected to the dipper stick 15 3,140,785 Patented July 14, 1964 at 23, is pivotally connected to ram 26 of hydraulic means 28 at 22.

Hydraulic means 28 serves to effect rotation of the bucket 19 relative to the dipper stick 15 and comprises the ram 26 pivotally connected to the link 25 and the second link 24 at 22 and the cylinder 27 pivotally connected at 29 to the dipper stick 15.

The hydraulic means 30 for pivoting the dipper stick 15 relative to the boom 10 comprises the ram 30a and the cylinder 30b. Said ram 30a is pivotally connected at 32 to the dipper-stick extension 15a; said cylinder 30b is pivotally connected at 31 to the boom 10.

The dipper stick 15 includes therein the hydraulic means 33, which hydraulic means 33 comprise the cylinder 33a and the ram 33b, said cylinder 33a being pivotally connected to the dipper stick 15 at 34, and said ram 3311 being pivotally connected to the dipper-stick extension 15a at 35.

Said hydraulic means 33 serves to control the movements of the dipper-stick extension 15a in relation to the dipper stick 15 such that said dipper-stick extension 15a may be caused to slide from its position shown in solid lines in FIG. 1 to its position shown in dotted lines in such figure, vice versa, or to any intermediate position. Such movement of the dipper-stick extension 15a serves to vary the distance between the pivot point of the boom 10 to the dipper stick 15 and the pivot point of the dipperstick pivoting-hydraulic means 30 to the dipper-stick extension 15a. This movement of the dipper-stick extension 15a, thereby, serves to change the leverage and the speed of operation of the apparatus and, hence, to change the speed of operation and the power of said apparatus. Furthermore, through said means the pivot points may be extended or retracted in minute increments.

More specifically, movement of the dipper-stick extension 15a such that the pivot points 14 and 32 move in close to one another provides more bucket rotation and a higher rate of operating speed. Movement of said dipperstick extension 15a such that said pivot points move further apart from one another, on the other hand, provides more power and less rotation of the bucket 19.

Although the means provided by the present invention are shown as controlled manually, said means may be constructed to be controlled either manually or automatically, as maybe desired, without departing from the spirit of the invention. Furthermore, instead of the hydraulic cylinder utilized in the illustration of the invention, a screw and nut or similar arrangement may be used to cause the extension and retraction of the pivot points. In the latter event, the bucket could be carried by a threaded or screw member and the adjustment of the length of the dipper stick controlled by means of an adjusting nut in operating engagement with said threaded or screw member.

The operation of the device is believed to be apparent from the foregoing description.

From the foregoing, it will be seen that I have provided a new and improved means for extending or retracting the pivot points in minute increments.

Furthermore, from the foregoing it will be seen that I have provided new and improved means for providing either additional power or additional speed, as may be desired, in the operation of a trencher, backhoe, or the like. Thus, it will be seen that I have provided new and improved means for adjusting the operation of such apparatus to fit the needs of operation.

From the foregoing, it will be seen that I have provided new and improved means for accomplishing all of the objects and advantages of the invention.

I claim:

1. In a device of the character described, a boom, a

dipper stick pivotally connected to said boom, said dipper stick including an adjustable extension and carrying a bucket adjacent its lower end, hydraulic means for pivoting said dipper stick relative to said boom, said hydraulic means being pivotally connected adjacent its opposite ends to said boom and said adjustable extension of said dipper stick, and means connecting said dipper stick and said adjustable extension thereof for varying the distance between the pivot connection of said dipper stick and said boom and the pivotal connection of said hydraulic means to said dipper stick extension such as to thereby vary the speed of operation and power of the apparatus.

2. In a device of the character described, a boom, a dipper stick pivotally connected to said boom, said dipper stick having an adjustable extension and carrying a bucket adjacent its lower end, hydraulic means for pivoting said dipper stick relative to said boom, said hydraulic means being pivotally connected adjacent its opposite ends to said boom and said adjustable extension of said dipper stick, means connecting said dipper stick and said adjustable extension thereof for varying the distance between the pivot connection of said dipper stick to said boom and the pivot connection of said hydraulic means to said dipper stick extension such as to thereby vary the power and speed of operation of the apparatus, and means for controlling said means for varying the distance between said pivot connections.

3. In a device of the character described, a boom, a dipper stick pivotally connected to said boom, said dipper stick having an adjustable extension and carrying a bucket adjacent its lower end, first hydraulic means for pivoting said dipper stick relative to said boom, said hydraulic means being pivotally connected adjacent its opposite ends to said boom and said dipper stick extension, second hydraulic means operatively connecting said dipper stick with said extension of said dipper stick such that the distance between the pivotal connections of said boom and said first hydraulic means to said dipper stick and said dipper extension, respectively, may be adjusted thereby varying the effective length of said dipper stick, and means for controlling said second hydraulic means.

4. In a device of the character described, a boom, a dipper stick pivotally connected to said boom, said dipper stick having a slidably adjustable extension and carrying a bucket adjacent its lower end, first hydraulic means for pivoting said dipper stick relative to said boom, said hydraulic means being pivotally connected adjacent its opposite ends to said boom and said dipper stick extension, second hydraulic means operatively connecting said dipper stick with said dipper stick extension and operable such as to cause movement of said dipper stick extension relative to said dipper stick and thereby to vary the effective distance between the pivotal connections of said boom and said first hydraulic means to said dipper stick and said dipper stick extension, respectively, and means for controlling said second hydraulic means.

5. In a device of the character described, a boom, a dipper stick pivotally connected to said boom, said dipper stick having a slidably adjustable extension and carrying a bucket adjacent its lower end, first hydraulic means for pivoting said dipper stick relative to said boom, said first hydraulic means being pivotally connected adjacent its opposite ends to said boom and said dipper stick extension, second hydraulic means connected to said dipper stick and said dipper stick extension for causing movement of said dipper stick extension relative to said dipper stick such as to thereby vary the distance between the pivot connection of said boom to said dipper stick and the pivot connection of said first hydraulic means to said dipper stick extension, said second hydraulic means being adapted to cause said relative movement of said dpiper stick and said extension thereof in minute increments, and automatic means for controlling said second hydraulic means.

References Cited in the file of this patent UNITED STATES PATENTS 1,162,607 Hoar Nov. 30, 1915 2,411,498 Billings Nov. 26, 1946 2,461,978 Hall Feb. 15, 1949 2,678,741 Pilch May 18, 1954 2,989,198 Bradley June 20, 1961 

1. IN A DEVICE OF THE CHARACTER DESCRIBED, A BOOM, A DIPPER STICK PIVOTALLY CONNECTED TO SAID BOOM, SAID DIPPER STICK INCLUDING AN ADJUSTABLE EXTENSION AND CARRYING A BUCKET ADJACENT ITS LOWER END, HYDRAULIC MEANS FOR PIVOTING SAID DIPPER STICK RELATIVE TO SAID BOOM, SAID HYDRAULIC MEANS BEING PIVOTALLY CONNECTED ADJACENT ITS OPPOSITE ENDS TO SAID BOOM AND SAID ADJUSTABLE EXTENSION OF SAID DIPPER STICK, AND MEANS CONNECTING SAID DIPPER STICK AND SAID ADJUSTABLE EXTENSION THEREOF FOR VARYING THE DISTANCE BETWEEN THE PIVOT CONNECTION OF SAID DIPPER STICK AND SAID BOOM AND THE PIVOTAL CONNECTION OF SAID HYDRAULIC MEANS TO SAID DIPPER STICK EXTENSION SUCH AS TO THEREBY VARY THE SPEED OF OPERATION AND POWER OF THE APPARATUS. 